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The future of zero emissions?

by Ron Ball Former Board Member, The Log

A view into ZeroAvia, and the development of hydrogen-powered aircraft.

Gloucestershire has a significant and proud history in the development of aircraft propulsion systems. The first flight of a jet-powered aircraft in the UK took place in Brockworth in 1941, when Sir Frank Whittle’s experimental E28/39 accomplished a few short hops of a distance slightly exceeding that of the Wright brothers’ inaugural flight. His aircraft was there to do ground testing. Brockworth had two claims to fame up til then. It was a base for the Gloster Aircraft Company – the company that was to produce the Meteor, the Allies’ first operational jet fighter – and it was home to the quirky and quintessentially British sport of rolling Double Gloucester cheese down Cooper’s Hill.

With that history (the jet, not the cheese), it seems wholly appropriate that ZeroAvia should choose the ex-RAF base at Kemble as the UK base for its development work. As the name of the company suggests, it is working towards the development of aircraft engines that will eventually produce zero emissions. On 19th January 2023, ZeroAvia’s modified Dornier 228 completed a 10-minute flight powered by a conventional turboprop on the right wing and a hydrogen-electric motor on the left. As a modified 19-seater, this is the largest aircraft to have flown employing this technology and marks a significant milestone in its development.

After completing the first flight, test pilot Jon Killerby said: “The flight went very smoothly. The system worked exactly as expected and we are confidently looking forward to expanding the test envelope in the next few weeks.”

The Problems

It is not surprising that aviation is being forced to confront pollution and sustainability. One of the consequences of 9/11 was to highlight the pollution that was being caused by the aviation industry. In the immediate aftermath, the almost total ban on flying imposed an effective ultra-low emissions zone over the United States and elsewhere, with measurable improvements in air quality. It was a powerful piece of evidence that the airline industry needed to clean up its act.

The Solutions

At the risk of oversimplifying the arguments, solutions fall into two camps. There are those who want to present flying as an antisocial pastime and wish to drastically prune the industry. Others – and ZeroAvia is firmly in this camp – believe it is possible to solve the technical problems that will enable us to continue to reap the huge benefits that aviation brings.

However, continuing as we are is not an option. Aviation is currently estimated to contribute about 5-10% of greenhouse gas emissions. Unchecked, that could rise to between 25% and 50% by 2050. Making matters worse is the fact that pollutants – including NOx gases – are released at high altitude, which may amplify their effects up to fourfold. It is against this backdrop that Val Miftakhov, co-founder and CEO, set up ZeroAvia in 2018 with a vision to produce commercially viable hybrid hydrogen/electric aircraft. The flight of the Dornier represents a major step in realising that vision.

Who is Involved?

Making technological advances in aviation does not come cheap. Besides vision, it requires innovation, commitment, financial clout and, not least, patience. Development is not, and never has been, a straight-line activity and success depends on acquiring partners and keeping them on board. Government money is always helpful and the British government has supported ZeroAvia’s development through the Hyflyer ll project.

High-profile, private and robust backers come from a range of sources, including Amazon, Bill Gates and international airlines, such as British Airways, Alaskan, United and American Airlines, the latter two of which have 100 powerplants on order. Pre-orders number 1,500 in total. Actual figures are no doubt commercially sensitive, but backing to the tune of $154 million has been secured and revenue from pre-orders will be materialising later this year. The first flight will have been a major confidence boost for investors.

The Technology

The challenges of producing a battery-powered aircraft look formidable. The holy grail of producing lightweight/high-capacity batteries looks a long way off, and producing a commercially viable aircraft using that technology looks even more remote.

Hydrogen fuel cell technology is up and running already. The Dornier’s powerplant is powered by two hydrogen fuel cell systems with battery assistance, which is required for high-power settings such as take-off. Batteries will be designed out of the next iteration because of the weight penalty they bring. The infrastructure plan will be different for different airports, but the most favoured option is for the hydrogen to be produced using electrolysis on site, which will do away with the need for fuel tankers. These engines will produce no carbon dioxide or NOx gasses and, because of the low-temperature water vapour exhaust of the non-combustion system, contrails can be mitigated. If this technology can be scaled up – and there is no reason why it can’t – the wind will be taken out of the sails of those arguing to stop us from flying. How ironic is that?

The Future

To an extent, the future is already here. Besides orders and pre-orders for powerplant, the company has a shortlist of possible manufacturing sites, with a decision expected later this year. Similarly, the company will shortly be selecting an airframe for its first commercial sales. It has been decided to start with the retrofit of an existing airframe type, obviating the need for time-consuming and expensive certification of a brand new one.

Britain is proud of its role in the development of aviation. After a slow start (as evidenced by all the French terms for fuselage, aileron and empennage) we eventually caught up and were at the forefront of the development of things such as the jet engine, jet travel, supersonic flight and automatic landings. Things are much more global now, and ZeroAvia is an international company, but it is good to see that it chose the UK in which to develop its powerplant. Clearly, the skills, know-how and innovation required are recognised here.

When Sir Frank Whittle was developing his jet engine, he couldn’t have imagined where his invention would ultimately lead. We can now look at the work being done by companies such as ZeroAvia and confidently predict that usable, clean aircraft will be replacing their antisocial predecessors in the foreseeable future. If continuity is your thing, however, you’ll be pleased to know that Brockhurst’s world-famous cheese rolling event is alive and well after a two-year Covid hiatus.


This article was originally featured in The Log, BALPA’s exclusive magazine for members. This, and many more exclusives, are published 3 times a year, and you can join now for access. Click here to explore our membership options. 

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